hp surestore auto path virtual array for Windows NT installation and user’s guide Version 1.03 Edition August 2001 Printed in U.S.A.
Notice Trademark Information © Hewlett-Packard Company, 2001. All rights reserved. Microsoft, Windows NT, and Windows 2000 are registered trademarks of Microsoft Corporation Hewlett-Packard Company makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose.
CONTENTS 1 Auto Path features 5 Auto Path description 6 Dynamic load balancing 7 Automatic failover and recovery 8 System requirements 9 Product Contents 10 Auto Path VA Upgrade Licenses 11 HP Modular Storage Software Products Warranty 13 Technical Support 13 2 Installation 15 Installing Auto Path software Uninstalling Auto Path 17 3 Operation 11 16 19 Configuring Auto Path using the graphical user interface Navigation 22 Servers window 24 Adding a server 26 Deleting a server 27 Refreshing the
Accessing Auto Path help 32 About window 33 Server Details window 34 Disk Arrays window 36 Devices window 37 Adding new devices and paths 39 Device Settings window 40 Setting the load balancing policy 42 Setting the preferred path 44 Path Performance window 46 Saving chart settings 49 Opening and restoring chart settings 50 Removing a plot from the chart 51 Changing settings 52 Adapters window 53 AdapterPathInfo window 55 Using Windows Performance Monitor 57 4 Command-line interface 59 autopath adapters
AUTO PATH FEATURES HP Auto Path provides automatic input/output (I/O) path failover and load balancing for host systems configured with multiple host adapters and connections to a disk array. Auto Path provides these features: • enhanced data availability • automatic path failover to an alternate path and path recovery • dynamic load balancing over multiple paths • both a graphical user interface (GUI) and a command-line interface (CLI) The GUI provides enhanced features, such as path performance windows.
Auto Path description The HP Auto Path software performs dynamic load balancing of data flow through multiple paths. It detects multiple paths to each logical device and distributes the data load among the paths for optimum performance. It automatically detects path failures and switches to alternate paths and also recovers the failed paths after they are restored. The user interface lets a system administrator define load balancing policies and preferred paths, and view device path information.
Dynamic load balancing Auto Path performs dynamic load balancing while monitoring each path to ensure that the I/O transaction is completed. The load balancing policy is selected by the administrator. The dynamic load balancing policy prevents any path from becoming overloaded, and it helps to prevent the congestion that occurs when many I/O operations are directed to common devices along the same path.
Automatic failover and recovery In the event of a failure of any part of a path between the disk array and a server, Auto Path automatically switches to an alternate path, dropping the failed path out of the I/O rotation without any loss of data. The failover is not visible to applications, so normal operation continues, without downtime. After the paths are restored, they are automatically detected and used for I/O. All path changes are logged in the Windows Event Viewer log.
System requirements To install Auto Path, the system must conform to these requirements: • Windows NT with service pack 6 • 30 MB of local disk space available on the Windows NT system • administrator access to the Windows NT system • preformatted devices on the attached disk array for recognition and use by Auto Path and Windows NT • 1024 x 768 minimum display resolution For specific installation requirements for your system, contact your HP account representative.
Product Contents The contents of the Auto Path VA product include: • HP StoreStore Auto Path Virtual Array Installation and User’s Guide • Software CD • 1 Host License-to-Use Certificate Installation and User’s Guide Software CD License-to-Use Certificate 10 HP Auto Path XP: User’s Guide (Windows NT/2000)
Auto Path VA Upgrade Licenses A one host license-to-use is required for each installation of Auto Path VA. Upgrade licenses provide additional host usage for the Auto Path VA product. These upgrade licenses can increase the host usage up to 25 hosts, depending on the license purchased (see Table 1 on page 12).
Table 1 HP Modular Storage Software Products Software Product HP Sales Rep. HP Reseller T1001A T1020A T1002A T1021A T1007A T1008A T1009A T1026A T1027A T1028A T1003A T1004A T1005A T1022A T1023A T1024A T1039A T1040A T1041A T1042A T1043A T1049A T1050A T1051A T1052A T1053A Command View SDM Storage device management enables array configuration and management and provides value-added software products.
Warranty This software package comes with a 90 day media defect warranty. If you have any problems with the quality of the CD or the supporting documentation, you can return it for exchange through any HP sales office or authorized HP reseller. Technical Support Technical support is provided for this product through an HP Support Contract, purchased at the time you purchased this product. See the HP Support Contract for information on technical support.
HP Auto Path XP: User’s Guide (Windows NT/2000)
INSTALLATION Auto Path is installed using an automated installation program. After Auto Path is installed, and the server software component is running on the host, Auto Path is accessible from a networked PC where the client software is installed.
Installing Auto Path software To install Auto Path, you must have administrator privileges on the host PC. Caution Read the readme.txt file on the installation media for more details about installation. To install Auto Path: 1. Log on as administrator. 2. Insert the Auto Path installation CD into a local CD-ROM drive (for example, drive D:). 3. If Autorun is enabled on the PC, the Auto Path installation window appears, and you can follow the instructions to complete the installation. 4.
Uninstalling Auto Path To uninstall Auto Path, use the Windows Control Panel. To uninstall Auto Path: 1. Open the Windows Control Panel. 2. Open Add/Remove Programs. 3. Select Auto Path. 4. Click the Add/Remove button. 5. Follow the on-screen instructions to uninstall the Auto Path program files.
HP Auto Path XP: User’s Guide (Windows NT/2000)
OPERATION Auto Path operations can be accessed from both a graphical user interface (GUI) and command line interface (CLI). Both the GUI and the CLI can be used to display information about the logical devices on an attached disk array and their associated I/O paths. The administrator can use the interface to change the load balance policy or the preferred path to a device.
Configuring Auto Path using the graphical user interface After installing Auto Path, you can start the Auto Path graphical user interface (GUI) program. To start the Auto Path GUI program, you must have administrator access to the server. To use the interface, you must start both the user-interface server and client GUI. Depending on the options that you selected during the installation, you can start the server and client using either an icon on the Windows desktop or from the Windows Start menu.
The Servers window opens. Example If this is the first time that Auto Path is opened after installation, the window shows localhost server by default. To add servers to the program, use the Add New Server window. See “Adding a server” (page 26).
Navigation The Auto Path GUI configuration windows feature a navigational tree structure that shows the distribution of servers, disk arrays, adapters, and devices in the system. At startup, the tree is automatically populated. Example Tree structure functionality Servers Root of the hierarchy that contains all configured servers as nodes. Select a server to display the Servers window; see “Servers window” (page 24). Server nodes Expand a server node to show DiskArrays and Adapters.
Operation Device nodes Device nodes are identified by device names. Select to display the Device Settings window; see “Device Settings window” (page 40). Adapters Node that contains adapters on the parent server. Select to display the Adapters window; see “Adapters window” (page 53). Expand to show adapter nodes. Adapter nodes Adapter nodes are identified by adapter names. Select to display the AdapterPathInfo window; see “AdapterPathInfo window” (page 55).
Servers window Auto Path opens with the Servers window. This window shows the names of the servers and the status of the Auto Path software on them. At startup, the tree in the left panel is automatically populated. To access this window, select Servers, the root of the tree structure. Example The Servers window displays server information: 24 Server # An index number used by Auto Path for identifying the server. Server Name The server name.
Status The status of the server: Auto Path Server Up The target server is operational. Auto Path Server Down The target server is down or it is not running the Auto Path GUI server. Operation Auto Path Driver Not Functioning The Auto Path driver is not running on the target server. Status update in progress The update of the Auto Path Server status is in progress.
Adding a server You can add a new server to the list of available servers for Auto Path by using the Add New Server dialog box. To add a server: 1. From the Servers window, select Add New Server from the File dropdown menu The Add New Server dialog box opens. Example 2. In the Server Name box, type the server name or the IP address for the server you want to add. 3. Select Add. The server name is added as a node on the Servers tree in the left panel of the Servers window.
Deleting a server You can delete a server from the list of available servers for Auto Path using the Delete Server dialog box. To delete a server: 1. From the Servers window, select Delete Server from the File drop-down menu. The Delete Server dialog box opens. Example 2. From the Select Server drop-down box, select the server name of the server you want to delete. 3. Select Delete. The node of the selected server is deleted from the Servers tree in the left panel of the Servers window.
Refreshing the window The View drop-down menu allows you to refresh the display to show the current state of the selected server/devices. Select Refresh.
Diagnostic message panel The main window provides a diagnostic message panel that displays error messages periodically for the active (selected) server. The error message panel is located in the bottom right portion of the window. Example The error messages are color coded: Operation red A connection to a server has been lost, or a device/path has disappeared. green A connection to a server is established, or a device/path has come up.
Error Log File For the default installation, error messages are recorded in an Auto Path log file: \hpss\Auto Path\data\autopath.log Set the log file size through the Set Log File Size command on the Options menu.
Server Settings window Use the Server Settings window to change the update times for the server status, device data, and path performance data.
Accessing Auto Path help Use the Help drop-down menu to access Auto Path help.
About window The About window displays the HP Auto Path version number.
Server Details window The Server Details window shows the disk arrays and adapters connected to the selected server. This window is a view-only window; there are no userconfigurable functions. To access the Server Details window, select the node of a server in the tree view. The content of the window depends on the connection status of the selected server.
Adapters A folder equivalent to the Adapters node in the tree view. Select to display the Adapters window; see “Adapters window” (page 53). The tree view expands to the level of the adapter nodes. Failed server connection If the client is not able to connect to the server, the main portion of the window appears empty. The status bar at the bottom of the window displays a message: Failed to connect to the server.
Disk Arrays window The Disk Arrays window shows the details of the disk arrays connected to the selected server. This window is a view-only window; there are no userconfigurable functions. To access the Disk Arrays window, select the Disk Arrays node of a server in the tree view. Example The Disk Arrays window displays disk array information: Disk Array # An index number used by Auto Path for identifying the disk array. Disk Array Name The serial number of the disk array.
Devices window The Devices window displays the devices for the selected disk array. This window is a view-only window; there are no user-configurable functions. To access the Devices window, select a disk array node in the tree view. Example The Devices window displays device information: Operation Device# An index number used by Auto Path for identifying the device. Device Name The device name. Serial# The logical device serial number.
State # of Paths The state of the device: Active The device is in use. Failed The device is not in use or all paths to the device have failed. The number of active paths attached to the device. Load Balance Policy The policy currently selected for the device. Preferred Path # 38 For devices with no load balancing policy, this indicates the selected preferred path.
Adding new devices and paths Windows NT When you add a new device or a new path to an existing device, you must run Windows Disk Administrator so that Auto Path can recognize it. To recognize new devices or paths in Auto Path: 1. Start Windows Disk Administrator by selecting Programs → Administrative Tools → Disk Administrator from the Windows Start menu. 2. After Disk Administrator is fully initialized and execution is finished, you must refresh the Auto Path GUI.
Device Settings window The Device Settings window shows the paths to a device and its load balance policy and preferred path to the device in case of No_Load_Balance policy. Access this window by selecting a device node in the tree structure. Example The Device Settings window displays device information: Load Balancing Policy Displays the load balancing policy for the device. The drop-down list lets you choose from a list of policies. See “Setting the load balancing policy” (page 42).
Path # The index number for the path. State The state of the path: Controller Port # Active The path to the device is available for I/O. Failed The path to the device is not available for I/O. The port number of the controller on the disk array to which the device is connected. Port.Bus.Target.LUN Displays the physical path identifier. Set Applies the changes. Cancel Cancels the operation.
Setting the load balancing policy The Device Settings window lets you set the load balancing policy for a selected device. All of the load balancing policies determine their actions based upon the current queue depths of all of the paths available to the device. The only difference between policies is how the queue depth is measured. All of the policies, except Round Robin, tend to shift the I/O load from heavily loaded paths or resources to more lightly loaded ones.
To set the load balancing policy: 1. From the tree view, select the server, disk array, and device that you want to set the load balancing policy for. The Device Settings window opens (see page 40). 2. Select the load balancing policy from the Load Balancing Policy dropdown list. The new load balancing policy is displayed. 3. Select Set. The load balancing policy is applied.
Setting the preferred path The Device Settings window lets you set the preferred path when you have no load balancing policy for a selected device. If the current policy is not No Load Balancing, set the Load Balance Policy to No Load Balancing for the device for which you want to set a preferred path. To set the preferred path: 1. From the tree view, select the server, disk array, and device that you want to set the preferred path for. The Device Settings window opens (see page 40). 2.
3. Select Set. The no load balancing policy and preferred path are applied.
Path Performance window The Path Performance window allows you to create and view performance charts for selected paths of a device. The charts can be used to evaluate load balancing policy or preferred paths. To access the Path Performance window, select the Path Performance button in the Device Settings window. The Path Performance window opens separately from the main Auto Path window. To close the window, select Exit from the File menu.
Chart parameters Paths Drop-down box that is used to select the index number of a path to be charted. Counter A list of available counters, measured on the y-axis of each chart. Choices are: % Disk Read Time % Disk Write Time % Disk Time % Idle Time Disk Read/sec Disk Writes/sec Disk Transfers/sec Current Disk Queue Length Disk Bytes/Sec Disk Read Bytes/Sec Disk Write Bytes/Sec Scale Drop-down box that is used to select the scale of the chart.
Device settings controls Load Balancing Policy Displays the load balancing policy for the device. The drop-down list lets you choose from a list of policies; see “Setting the load balancing policy” (page 42). Preferred Path Number (Displayed only when No Load Balancing is selected for Load Balancing Policy.) Displays the index number of the preferred path for the device. Select the preferred path to a device from the drop-down list. Set Applies the changes. Cancel Cancels the operation.
Saving chart settings You can save the settings of a chart for future use using the Save Chart Settings option. To save chart settings: 1. Select Save Chart Settings from the File menu. The Save Chart Settings window appears. Example 2. Enter a filename with the extension .app. 3. Select Save. The chart settings are saved for future use. To open a chart settings file, see “Opening and restoring chart settings” (page 50).
Opening and restoring chart settings You can restore previously saved chart settings by opening a chart settings file. To create a chart settings file, see “Saving chart settings” (page 49). To open a chart settings file: 1. Select Open from the File menu. The Open Chart Settings File window appears. Example 2. Select the desired chart settings file. Chart settings files use the extension .app. 3. Select Open. The chart settings are restored.
Removing a plot from the chart You can remove an unwanted plot from the chart using the Delete From Chart option. To delete a plot from the chart: 1. Select the Path # of the plot you want to delete. 2. Select Delete From Chart from the Edit menu. Example The plot is removed from the chart.
Changing settings You can change the vertical maximum of a chart using the Chart Settings dialog box. To change the vertical maximum of a chart: 1. Select Chart Settings from the Options menu. The Chart Settings window opens. Example 2. Enter the vertical maximum. 3. Select OK. The new vertical maximum is applied.
Adapters window The Adapters window lists all the Auto Path-capable adapters on the system. This window is a view-only window, and there are no userconfigurable functions. Example The Adapters window displays adapter information: Operation Adapter # An index number used by Auto Path for identifying the adapter. Adapter Name The name of the adapter. Adapter State The state of the adapter: Active The adapter is in use. Failed The adapter has failed.
# of Paths The number of paths through the adapter. Adapter SCSI Port # The adapter SCSI port number.
AdapterPathInfo window The AdapterPathInfo window shows the details of the various paths through the adapter. This window is a view-only window; there are no userconfigurable functions. To access the AdapterPathInfo window, select an adapter under the Adapters node in the tree view. Example The AdapterPathInfo window displays path information: Path # Operation An index number used by Auto Path for identifying the path.
Path State The state of the path: Active The path to the device is available for I/O. Failed The path to the device is not available for I/O. Port.Path.Target.LUN Displays the physical path identifier. 56 Device Name The name of the device that the path leads to. Device Serial # The serial number of the device that the path leads to.
Using Windows Performance Monitor Windows Performance Monitor also allows you to create and view performance charts for selected paths of a device. The charts can be used to evaluate load balancing policy or preferred paths. To create a path performance chart using Performance Monitor: 1. Start Windows Performance Monitor by selecting Programs → Administrative Tools → Performance Monitor from the Windows Start menu. The Performance Monitor window opens. 2. Select Add to Chart from the Edit menu.
HP Auto Path XP: User’s Guide (Windows NT/2000)
COMMAND-LINE INTERFACE The Auto Path command-line interface (CLI) can be used only on hosts connected to multipath-capable devices with the Auto Path driver installed. The commands supported by this interface and the syntax are described here: • autopath adapters (page 60) • autopath devices (page 61) • autopath help (page 62) • autopath paths device (page 63) • autopath set device (page 64) You can execute Auto Path commands only from the directory where the installed Auto Path program files reside.
autopath adapters autopath adapters Display adapter names Syntax Description Example autopath adapters The autopath adapters command is used to display the various adapters in the system.
autopath devices autopath devices Display devices Syntax Description autopath devices The autopath devices command displays the details of the multipathcapable devices in the system. Example HP Auto Path> autopath devices Device # Device Name Serial No.
autopath help autopath help Display help Syntax Description autopath help The autopath help command opens the help for the autopath commandline interface supported commands.
autopath paths device autopath paths device Display paths to device Description Syntax The autopath paths device command displays the paths to the selected device referenced by the device number. autopath paths device=device_number device_number Example The Auto Path index number shown in the autopath devices command line display. The device for this example has a defined load balancing policy.
autopath set device autopath set device Set load-balancing policy or preferred path Syntax Description autopath set device=device_number { policy=policy_name | path=path_number } device_number The Auto Path index number shown in the autopath devices command line display. policy_name The load balancing policy name. For a list of load balancing policies, see “Setting the load balancing policy” (page 42). path_number The preferred path number.
TROUBLESHOOTING Troubleshooting can be performed by the customer or an HP service representative, depending on your HP service contract. If you are unable to resolve an error condition, ask your HP service representative for assistance.
Recovering after a failure When a path fails, it is no longer used by Auto Path. After the path is returned to normal, Auto Path automatically begins using the path with the designated load balancing policy. No user action is necessary. If there is no load balancing policy set for a failed path and the path was not set as the preferred path, no user action is necessary.
Troubleshooting To troubleshoot Auto Path, you can use these troubleshooting tools: • Event Viewer The Event Viewer logs path failovers/recovery, disk and adapter errors, and I/O errors. • Windows Diagnostics The Administrative Tools utility, accessed from the Windows Control Panel, shows all devices connected to the Windows system. • Windows Registry Caution Back up the Registry before executing the Registry Editor. The Registry shows the devices connected to the Windows system.
Contacting HP customer service If you call HP customer support, provide as much information about the problem as possible, including the circumstances surrounding the error or failure and the exact content of any error messages displayed on the host system.
INDEX A About window description 33 AdapterPathInfo window description 55 Adapters window description 53 autopath adapters syntax description 60 autopath devices syntax description 61 autopath help syntax description 62 autopath paths device syntax description 63 autopath set device syntax description 64 C Chart Settings dialog box description 52 D Device Settings window description 40 devices adding 39 Devices window description 37 refreshing information 28 Diagnostic Message panel description 29 Disk Ar
I installation deinstalling 17 procedure 16 requirements 9 L load balancing description 7 load balancing policy list 42 setting 42 P path performance chart opening and restoring settings 50 saving settings 49 Path Performance window description 46 paths adding 39 setting preferred 44 starting Auto Path GUI how to 20 T troubleshooting HP customer support 68 W warranty 13 windows About 33 AdapterPathInfo 55 Adapters 53 Device Settings 40 Devices 37 Disk Arrays 36 Path Performance 46 Server Details 34 Server
